K1C20_RAT
ID K1C20_RAT Reviewed; 429 AA.
AC P25030;
DT 01-MAY-1992, integrated into UniProtKB/Swiss-Prot.
DT 19-SEP-2002, sequence version 2.
DT 25-MAY-2022, entry version 110.
DE RecName: Full=Keratin, type I cytoskeletal 20;
DE AltName: Full=Cytokeratin-20;
DE Short=CK-20;
DE AltName: Full=Cytokeratin-21;
DE Short=CK-21;
DE AltName: Full=Keratin-20;
DE Short=K20;
GN Name=Krt20; Synonyms=Krt21;
OS Rattus norvegicus (Rat).
OC Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia;
OC Eutheria; Euarchontoglires; Glires; Rodentia; Myomorpha; Muroidea; Muridae;
OC Murinae; Rattus.
OX NCBI_TaxID=10116;
RN [1]
RP NUCLEOTIDE SEQUENCE [MRNA], AND TISSUE SPECIFICITY.
RC STRAIN=Sprague-Dawley; TISSUE=Intestinal epithelium;
RX PubMed=1711044; DOI=10.1016/s0021-9258(18)99047-2;
RA Chandler J.S., Calnek D., Quaroni A.;
RT "Identification and characterization of rat intestinal keratins. Molecular
RT cloning of cDNAs encoding cytokeratins 8, 19, and a new 49-kDa type I
RT cytokeratin (cytokeratin 21) expressed by differentiated intestinal
RT epithelial cells.";
RL J. Biol. Chem. 266:11932-11938(1991).
RN [2]
RP TISSUE SPECIFICITY, AND DEVELOPMENTAL STAGE.
RX PubMed=7689500; DOI=10.1111/j.1432-0436.1993.tb00649.x;
RA Calnek D., Quaroni A.;
RT "Differential localization by in situ hybridization of distinct keratin
RT mRNA species during intestinal epithelial cell development and
RT differentiation.";
RL Differentiation 53:95-104(1993).
RN [3]
RP PHOSPHORYLATION [LARGE SCALE ANALYSIS] AT SER-13; SER-16 AND SER-26, AND
RP IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
RX PubMed=22673903; DOI=10.1038/ncomms1871;
RA Lundby A., Secher A., Lage K., Nordsborg N.B., Dmytriyev A., Lundby C.,
RA Olsen J.V.;
RT "Quantitative maps of protein phosphorylation sites across 14 different rat
RT organs and tissues.";
RL Nat. Commun. 3:876-876(2012).
CC -!- FUNCTION: Plays a significant role in maintaining keratin filament
CC organization in intestinal epithelia. When phosphorylated, plays a role
CC in the secretion of mucin in the small intestine (By similarity).
CC {ECO:0000250}.
CC -!- SUBUNIT: Heterotetramer of two type I and two type II keratins.
CC Associates with KRT8 (By similarity). {ECO:0000250}.
CC -!- TISSUE SPECIFICITY: Expressed predominantly in the intestinal
CC epithelium in differentiated villus cells. {ECO:0000269|PubMed:1711044,
CC ECO:0000269|PubMed:7689500}.
CC -!- DEVELOPMENTAL STAGE: Becomes apparent upon completion of villus
CC formation at 20 days gestation (2 days before birth) and is expressed
CC by the entire epithelium of the villus. {ECO:0000269|PubMed:7689500}.
CC -!- PTM: Hyperphosphorylation at Ser-13 occurs during the early stages of
CC apoptosis but becomes less prominent during the later stages.
CC Phosphorylation at Ser-13 also increases in response to stress brought
CC on by cell injury (By similarity). {ECO:0000250}.
CC -!- PTM: Proteolytically cleaved by caspases during apoptosis. Cleavage
CC occurs at Asp-233 (By similarity). {ECO:0000250}.
CC -!- MISCELLANEOUS: There are two types of cytoskeletal and microfibrillar
CC keratin: I (acidic; 40-55 kDa) and II (neutral to basic; 56-70 kDa).
CC -!- SIMILARITY: Belongs to the intermediate filament family.
CC {ECO:0000255|PROSITE-ProRule:PRU01188}.
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DR EMBL; M63665; AAA41473.1; -; mRNA.
DR PIR; A40452; A40452.
DR RefSeq; NP_775151.1; NM_173128.1.
DR AlphaFoldDB; P25030; -.
DR SMR; P25030; -.
DR IntAct; P25030; 3.
DR iPTMnet; P25030; -.
DR PhosphoSitePlus; P25030; -.
DR jPOST; P25030; -.
DR PRIDE; P25030; -.
DR GeneID; 286912; -.
DR KEGG; rno:286912; -.
DR UCSC; RGD:628646; rat.
DR CTD; 54474; -.
DR RGD; 628646; Krt20.
DR InParanoid; P25030; -.
DR OrthoDB; 798081at2759; -.
DR PhylomeDB; P25030; -.
DR Reactome; R-RNO-6805567; Keratinization.
DR Reactome; R-RNO-6809371; Formation of the cornified envelope.
DR PRO; PR:P25030; -.
DR Proteomes; UP000002494; Unplaced.
DR GO; GO:0005737; C:cytoplasm; ISO:RGD.
DR GO; GO:0005856; C:cytoskeleton; IBA:GO_Central.
DR GO; GO:0005882; C:intermediate filament; IEA:UniProtKB-KW.
DR GO; GO:0005198; F:structural molecule activity; IEA:InterPro.
DR GO; GO:0006915; P:apoptotic process; IEA:UniProtKB-KW.
DR GO; GO:0009267; P:cellular response to starvation; ISS:UniProtKB.
DR GO; GO:0030855; P:epithelial cell differentiation; IBA:GO_Central.
DR GO; GO:0045109; P:intermediate filament organization; ISS:UniProtKB.
DR GO; GO:0050708; P:regulation of protein secretion; ISS:UniProtKB.
DR InterPro; IPR018039; IF_conserved.
DR InterPro; IPR039008; IF_rod_dom.
DR InterPro; IPR002957; Keratin_I.
DR PANTHER; PTHR23239; PTHR23239; 1.
DR Pfam; PF00038; Filament; 1.
DR PRINTS; PR01248; TYPE1KERATIN.
DR SMART; SM01391; Filament; 1.
DR PROSITE; PS00226; IF_ROD_1; 1.
DR PROSITE; PS51842; IF_ROD_2; 1.
PE 1: Evidence at protein level;
KW Apoptosis; Coiled coil; Intermediate filament; Keratin; Phosphoprotein;
KW Reference proteome.
FT CHAIN 1..429
FT /note="Keratin, type I cytoskeletal 20"
FT /id="PRO_0000063676"
FT DOMAIN 75..386
FT /note="IF rod"
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU01188"
FT REGION 1..74
FT /note="Head"
FT REGION 1..26
FT /note="Disordered"
FT /evidence="ECO:0000256|SAM:MobiDB-lite"
FT REGION 75..110
FT /note="Coil 1A"
FT REGION 111..128
FT /note="Linker 1"
FT REGION 129..220
FT /note="Coil 1B"
FT REGION 221..243
FT /note="Linker 12"
FT REGION 244..382
FT /note="Coil 2"
FT REGION 383..429
FT /note="Tail"
FT COMPBIAS 8..26
FT /note="Polar residues"
FT /evidence="ECO:0000256|SAM:MobiDB-lite"
FT SITE 233..234
FT /note="Cleavage; by caspases"
FT /evidence="ECO:0000250"
FT MOD_RES 13
FT /note="Phosphoserine"
FT /evidence="ECO:0007744|PubMed:22673903"
FT MOD_RES 16
FT /note="Phosphoserine"
FT /evidence="ECO:0007744|PubMed:22673903"
FT MOD_RES 26
FT /note="Phosphoserine"
FT /evidence="ECO:0007744|PubMed:22673903"
SQ SEQUENCE 429 AA; 49388 MW; 95CCA2ABB0F0028C CRC64;
MDFSRRSFHR SLSSSSQGPA LSTSGSLYRK GTMQRLGLHS VYGGWRHGTR ISVSKTTMSY
GNHLSNGGDL FGGNEKLAMQ NLNDRLASYL EKVRSLEQSN SKLEAQIKQW YETNAPSTIR
DYSSYYAQIK ELQDQIKDAQ IENARCVLQI DNAKLAAEDF RLKFETERGM RITVEADLQG
LSKVYDDLTL QKTDLEIQIE ELNKDLALLK KEHQEEVEVL RRQLGNNVNV EVDAAPGLNL
GEIMNEMRQK YEILAQKNLQ EAKEQFERQT QTLEKQVTVN IEELRGTEVQ VTELRRSYQT
LEIELQSQLS MKESLERTLE ETKARYASQL AAIQEMLSSL EAQLMQIRSD TERQNQEYNI
LLDIKTRLEQ EIATYRRLLE GEDIKTTEYQ LNTLEAKDIK KTRKIKTVVE EVVDGKVVSS
EVKEIEENI
